TNF-alpha inhibitors in systemic vasculitides and connective tissue diseases

The introduction of TNF-alpha inhibitors in the treatment of rheumatoid arthritis and several other diseases meant a major progress in the management and to the understanding of these chronic inflammatory diseases. In this article, the evidence of the role of TNF-alpha and for TNF-alpha inhibitors in systemic vasculitides and connective tissue diseases is reviewed. TNF-alpha is expressed in inflammatory lesions. TNF-alpha acts as a proinflammatory cytokine in most disease processes analyzed so far, but it might have anti-inflammatory properties under certain conditions as well, e.g. with respect to B-cell regulation in systemic lupus erythematosus. It is not clear to what extent such aspects will be important in the treatment of connective tissue diseases and systemic vasculitides with TNF-alpha inhibitors. So far, most case reports and case series have suggested favourable results with TNF-alpha inhibitor therapy in systemic lupus erythematosus, dermato- and polymyositis, giant cell arteritis, Churg-Strauss syndrome, Wegener's granulomatosis and microscopic polyangiitis. Results of randomized, placebo-controlled trials are awaited for several connective tissue diseases and systemic vasculitides. One randomized, placebo-controlled trial has found no efficacy of infliximab treatment in primary Sjögren's syndrome recently.